Also refer to the “Renewable and alternative energy” page.
Energy is indispensable to the modern economy. Without it, all plans for growth and prospects for jobs come to nothing. An unreliable nature of electricity supply is one cause for lacklustre growth in any economy, and has seen nationwide alarm since 2019, and especially in 2023. (Refer to the last heading on this page for updates from the media).
There are many applications in the agricultural value chain which require a constant, uninterrupted flow of electricity (under the next heading several of these are set out). A disruption of power at an operation like an abattoir is not only inconvenient but can lead to much suffering.
Not only the availability of power but the pricing is important. Year-on-year double digit price increases over the past years have squeezed margins and the threatened the competitiveness of the agricultural sector. Agriculture has called on government and ESKOM to change its mindset about energy.
Two positives from the energy challenge are the resulting integration with neighbouring states that arise out of energy corridors, and the attention that is being given to renewables. Increasing the supply from private co-generation would be an effective way to alleviate the constraints. The Independent Power Producer Programme attracted billions of rand investment, but the country’s progress with this option has thus far been frustrating.
As a farmer you are a businessman, someone who is just as concerned about keeping operational costs under control as you are about your fields, crops and cattle.
As a farmer, you also know that energy costs are rising and adding significantly to operating costs. Controlling these costs means becoming more aware of energy and the ways you can use electricity more effectively without compromising your farm’s productivity.
By making small changes to the way you use power, you can ensure that you get the best value for your “energy rand” and also play a part in reducing the demand for power – especially in peak periods when the possibility of load shedding is always present.
You can make a start on effective power saving by looking at your operation and assessing the equipment you use and the tasks you use it for.
If you use dryers on your farm, remember that they can be shut down during the drying process, or can even be switched off completely. Alternatively, heating elements can be switched off and only the fans left running. Fans can be switched off for short periods without causing damage to produce such as grains, oil seeds and lucerne in the dryer. Only use the heating elements in the case of emergencies, for example during continuously rainy days and at night during the off-peak hours. When using heat, it is essential to recirculate the heated air to the inlet of the fan as this will save energy and costs.
When heating elements are used, it is advisable to insulate the ducting to minimise heat loss through the sides. It is vital that there should be no leaks in the ducting.
Making it less costly means that you should match the pipe and nozzle sizes. You should also remember that pipes with a small diameter operate at higher friction levels. More electricity is therefore needed to increase the rate of water delivery and overcome the friction.
The nozzle sizes of sprayers should be checked on a regular basis. If you reduce the wear and tear, you reduce water losses due to leaking pipes. Leaking pipes mean that pumps have to deliver more water and this increases the electricity consumption. By carrying out regular maintenance, you benefit from reduced power costs and water savings.
Using cellphone and computer technology could result in major savings. It’s a fact that if you use these methods to schedule irrigation, you can save up to 30% of the energy you generally use. Making sure that water is pumped to storage dams above irrigated areas means that you can use gravity flow, even when power is not available.
Electric motors consume vast amounts of power. The older your motors are, the higher the chances are that they use more electricity than they should. You can reduce your bills significantly by replacing these motors with new generation “high efficiency” electric motors (Eff 1). Make sure that the motors you install can run at 3/4 of their capacity to perform everyday jobs. Running at full load for long periods requires much more power.
Saving power in the dairy parlour means rinsing the milking machines with cold water directly after milking. A complete washing cycle should take place outside Eskom’s peak hours.
Ice bank cool tanks can be used to build the ice bank during off-peak hours to pre-cool and cool milk during Eskom’s peak hours.
You save electricity by keeping the doors to cold rooms properly sealed. Opening doors only when required cuts down on cold air being “leaked” into neighbouring areas. You should always also remember that overfilled coldrooms actually have a lower cooling efficiency. Air does not flow as easily between and under produce in overfilled rooms. This means that it takes longer to cool down your produce and that more electricity is needed to reach the storage temperature.
Condensers should be well ventilated to deliver the best performance. For greatest effectiveness, compressor rooms and condensers should be installed on the southern side of a building, where they are not affected by direct sunlight. You should check filters and coils regularly and see that they are always clean, and also make sure that there is enough gas in the air conditioning plant. The proper use of air curtains will also reduce the loss of conditioned air.
Coldrooms are major users of electricity. If you take several simple steps, however, cold losses can be minimised and you will benefit from lower electricity costs.
Reducing the cost of animal housing begins with the building itself. Proper roof insulation ensures a cool environment throughout the year and means that less money has to be spent on additional energy to regulate temperatures. Painting a roof silver will also reflect more heat off the structure.
When using natural ventilation for animal housing, buildings should not be wider than 12 metres for optimum utilisation of wind cooling.
If you are building animal housing, remember that the long walls of the building should face north and south and the short walls should face west and east. This will help to dispel the heat that builds up inside buildings during the day.
Animal feed processing plants usually have large numbers of electric motors. By installing a capacitor bank you can generally improve the electrical efficiency of a plant. A plant can be managed so that cleaning and operations requiring low electricity can be done during peak hours, and scheduling the actual operations outside Eskom’s peak hours.
When you build greenhouses, bear in mind that a double-insulated plastic cover retains more heat and warmth in greenhouses. Keeping air and soil temperatures constant through insulation means that less energy has to be used to create warmth in the greenhouse environment.
Improving insulation and optimising ventilation systems in broiler houses are crucial for curbing energy costs, particularly in winter.
As a farmer you can take steps to utilise the waste generated through normal farming operations to create energy. Harnessing the power of the sun can also save energy costs – over the years, these can add up to considerable savings and transform the way you do business.
Where considerable amounts of animal waste are present, you could investigate the possibility of using biogas installations to generate heat and electricity. These installations take the heat generated by animal waste and enable it to be piped into feedlots and piggeries for use as heating, or used for the production of cheap electricity.
If you wish to generate emergency power for short periods, consider purchasing a standby generator. Running off petrol or diesel, these generators are custom-made for various outputs. You should consider the amount of energy you will need and seek advice from an expert when considering an installation. Keep in mind that generators should only be used in well-ventilated spaces (be careful of the carbon monoxide build-up!) and should be far enough away from buildings so that their noise does not disturb people or animals.
There are a number of options available to utilise solar power. You should investigate which of the various options available would suit you best. Solar panels can be used to supply electricity for pumping, charging batteries for lights and any other low wattage use. However, they can be expensive, have a lifespan of approximately ten years and are vulnerable to hail and theft. They also need to be cleaned regularly as dust can reduce their efficiency.
Effective water heating can be provided through a network of black polythene and copper piping through which water is pumped. This can be installed on a roof and used to heat water for the house and/or swimming-pool.
Wind energy can be used to charge batteries that can supply power to low wattage equipment in households. Where water flows constantly from a high point, the water flow can be used to generate electricity.
Dual fuel systems are generally used for heating air or water in a heating system. They are frequently used for drying and intensive animal-housing operations.
The working principle is based on using heating elements during Eskom’s off-peak hours and alternative fuel during Eskom’s peak hours. Alternative fuel options are coal, gas, diesel, oil, paraffin, wood, stalks or any other medium that is readily available in the area.
The bottom line for energy efficiency is that we all bear the responsibility of doing what we can to save power. As a farmer, you have a significant role to play. You will also benefit by making your operations more cost-effective and energy-efficient – saving money while you help our country.
Source: ESKOM
Further reference:
Associations, pressure groups & NGOs
Relevant documents are the Integrated Resource Plan (IRP2019), National Development Plan (NDP), the Energy White Paper, and the Transmission Development Plan 2022-2031 (TDP2022). The TDP2022 is a “a living document” – to the country’s energy developments, particularly the Integrated Resource Plan of 2019 (IRP 2019).
Further reference:
The seventh of the Sustainable Development Goals (SDGs) is “Ensure access to affordable, reliable, sustainable and modern energy for all”. See https://sustainabledevelopment.un.org/sdg7. The Energy Progress Report can be read at https://trackingsdg7.esmap.org.
Some role players in the provision of electricity in Sub-Saharan Africa:
Read about energy supply in the SADC region at www.sadc.int.
